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| n | a(n) |
|---|---|
| 2 | -1 |
| 3 | 2 |
| 4 | 8 |
| 5 | 32 |
| 6 | 96 |
| 7 | -1024 |
| 8 | 512 |
| 9 | 2048 |
| 10 | 40960 |
| 11 | 32768 |
| 12 | 1572864 |
| 13 | -33554432 |
| 14 | 2097152 |
| 15 | 8388608 |
| 16 | 234881024 |
| 17 | 536870912 |
| 18 | 20937965568 |
| 19 | 8589934592 |
| 20 | 34359738368 |
| 21 | -73392401154048 |
| 22 | 549755813888 |
| 23 | 2199023255552 |
| 24 | -8796093022208000 |
| 25 | -1577385769486516224 |
| 26 | 11258999068426240 |
[-1,2,8,32,96,-1024,512,2048,40960,32768,1572864, -33554432,2097152,8388608,234881024,536870912, 20937965568,8589934592,34359738368, -73392401154048,549755813888,2199023255552, -8796093022208000,-1577385769486516224, 11258999068426240] |